# #Algorithm learned in Python

## Introduction

Implement the basic algorithm in Python to deepen your understanding of the algorithm. As the ninth bullet, we deal with linear search.

## Linear search

Search: Finding the data you want from a lot of data Linear: Examine in order from the beginning

In other words, linear search does not do anything complicated, but searches from the front in order.

## Programmatic linear search

Store the data in the list and check it in order from the beginning. This is a very simple program structure and easy to implement ⇒ ** Effective method when the number of data is small **

## Implementation

The code of the linear search and the output at that time are shown below.

#### `linear_search.py`

``````
"""
2020/12/21
@Yuya Shimizu

Linear search
"""
#Linear search function
def linear_search(data, target):
for i in range(len(data)):
if data[i] == target:
return i
return False

if __name__ == '__main__':
data = [50, 20, 70, 60, 40, 90, 30] #Target data to be searched
target = 40  #Value to search
found = linear_search(data, target)

else:
print(f"{target} is found at data[{found}]")
``````
##### output
``````40 is found at data
``````

Next, the output result when False is returned is also shown.

##### output
``````45 is not found in the data
``````

## A brief description of the linear search function

It is turned by the `for` statement, but since we want to return the index of the data as the return value, we dare to use`for i in range (len (data))`. Also, by `return` in` for`, it can be expressed by simply writing `return False` outside the` for` statement that the search result cannot be found.

## Impressions

Linear search is very simple and overlaps with intuition. I think it will be the basis for other searches. I am looking forward to learning from now on.

## References

Introduction to algorithms starting with Python: Standards and computational complexity learned with traditional algorithms Written by Toshikatsu Masui, Shoeisha